@Aethos:
and why would we need to know that exactly unless it would be something plot important? Most people at the end of part one pretty much guessed Obito gave Kakashi his eye. So what else is Kakashi Gaiden besides information that we should have needed when Tobi came around?
Or are you just saying that Kakashi Gaiden was one huge waste of a flashback?
It's no less relevant than every one piece characters flashback.
Just because we saw Saul in Robin's flashback, doesn't mean that because he doesn't come back from the grave and go apeshit on aokiji, that the f;ashback was a waste.
It was again, to separate the 2 parts, by showing the backstory of a character we knew nothing about.